The experimental Silkote paper was printed from plate 25061,according to the 2008 Durland, plate no. 25061 was used for both dry-printed (Scott 1033) and Silkote paper (Scott 1033a).
Per the note in the Scott's Specialized, both of those plates were also used to print No. 1033 on normal paper and competent expertization is required for 1033a.
Since you have both plates you can check paper yourself before seeking an Opinion. The silkote paper is a much denser stronger and a bit shinier paper than the standard paper. Under 10x magnification you should see a difference on 25061 versus 25062. If you do see a difference then get the Opinion. From the scan it appears they are more than likely to be standard 1033. Good luck though! Note silkote is not chalky.
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